Risk of hospitalization due to pneumococcal pneumonia in adults in Spain. The CORIENNE study

Background and objective: Pneumococcal pneumonia (PP) causes a high burden of disease in adults, however little is known about how the disease burden differs by underlying conditions and/or age. In order to guide recommendations for vaccination in adults, identification at national level of the relevant risk factors for PP is needed. Methods: This retrospective study used the national surveillance system for hospital data maintained by the Ministry of Health using code 481 (ICD-9-CM) for patients aged ≥18y from 1 January to 31 December 2011. Prevalence of comorbidities considered as risk factors for pneumococcal disease in the general population was estimated from the International Classification Primary Care maintained by the Autonomous Region of Madrid. Results: 11,844 cases were identified using code 481. Mean age: 71.5y. 81.1% of total patients had ≥1 comorbidity. Patients with at least 1 comorbidity showed higher mortality rate (1.2 vs 0.5;p<0.01), fatality rate (7.7% vs 5.7%;p<0.01), LoS (9.6 vs 8.4days) and costs (4,935 vs 4,250 €;p<0.01) than patients without comorbidities. Table 1 shows estimated annual incidence rate of hospitalization and OR by risk in Spain. Conclusion: The highest incidence rate of hospitalized PP was among adults aged ≥65 years. Comorbidities increase the risk of PP especially in adults below 65 years of age. These results provide evidence for pneumococcal prevention strategies.